perf: Add build id data in mmap2 event
Adding support to carry build id data in mmap2 event.
The build id data replaces maj/min/ino/ino_generation
fields, which are also used to identify map's binary,
so it's ok to replace them with build id data:
union {
struct {
u32 maj;
u32 min;
u64 ino;
u64 ino_generation;
};
struct {
u8 build_id_size;
u8 __reserved_1;
u16 __reserved_2;
u8 build_id[20];
};
};
Replaced maj/min/ino/ino_generation fields give us size
of 24 bytes. We use 20 bytes for build id data, 1 byte
for size and rest is unused.
There's new misc bit for mmap2 to signal there's build
id data in it:
#define PERF_RECORD_MISC_MMAP_BUILD_ID (1 << 14)
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/bpf/20210114134044.1418404-4-jolsa@kernel.org
2 files changed